A new algorithm for interpolating the missing data between two adjacent medical images is presented. Our method is useful for solving the interpolation of any region-represented images of an object to be reconstructed, even when the object is stretched abruptly, branched or hollow, as often occurs in medical images, which cases can not be handled well by existing methods. When this algorithm is applied, the nonoverlapped regions of the same object in the two base images are first extracted and encoded by chamfer distance code on every pixel in these regions. Then, the outer edges of the nonoverlapping regions are shrunk inward simultaneously so that the stretched edges reach the edges of the overlapping regions at the same time. The distance codes in nonoverlapping regions are used to limit the shrinking of these edges in the interpolation process. The proposed method also provides object centralization and enlargement operations to obtain stable and reasonable results in complicated case. The experimental results show that the proposed method is more efficient in resolving general interpolation tasks than the existing methods (S.P. Raya and J. K. Udupa, IEEE Trans. Med. Image. 9, 32-42, 1990; G. T. Herman et al., IEEE Comput. Graph. Appl. 12, 69-79, 1992; J.F. Guo et al., Comput. Med. Imag. Graph. 19, 267-279, 1995.)

Algorithms↗

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Three-dimensional characteristics of cartilaginous and bony components of dysplastic hips in children: three-dimensional computed tomography quantitative analysis.

A cartilage-viewing technique was developed to overcome the shortcoming of not seeing the cartilaginous components, believed to play more important role than the osseous components in children's hips, with computed tomography. This technique was applied to 25 dysplastic hips in children younger than 10 years to evaluate their global and local deficiencies. The findings helped us to understand more about their individual problems. To quantify the three-dimensional (3-D) parameters of acetabular anatomy and femoral head coverage, a measuring technique was developed based on digitization of the 3-D coordinates and fitting of every component of the hip. The improved images and the quantified parameters were expected to aid the planning, formulation, and even simulation of individualized surgical treatment for children with developmental dysplasia of the hip.

Acetabulum↗

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Intraoperative instability for developmental dysplasia of the hip in children 12 to 18 months of age as a guide to Salter osteotomy.

There is still debate on the necessity of Salter osteotomy for developmental dysplasia of hip (DDH) between 12 and 18 months of age. The goals of this study were to investigate the correlating factors of intraoperative instability as a guide to the additional Salter osteotomy and to evaluate the radiographic and clinical results. Stability could not be achieved in 63% of 84 hips with soft-tissue releases alone. The existence of three pathologic findings (grade of dislocation, inverted labrum, and excessive anteversion) and absence of two surgical procedures (transverse acetabular ligament incision and iliopsoas osteotomy) significantly correlates with instability. At follow-up, the acetabular remodeling with or without Salter osteotomy was similar. We conclude that the Salter osteotomy does not interfere with the acetabular remodeling and has no major disadvantages for children at that age but can help to improve the stability of the hip.

Age Factors↗

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Cytologic changes in hepatocellular carcinoma after percutaneous acetic acid injection. Correlation with helical computed tomography findings.

OBJECTIVE: To illustrate the cytologic features of hepatocellular carcinoma (HCC) after percutaneous acetic acid injection (PAI) and to correlate the cytologic findings with helical computed tomography (CT) findings. STUDY DESIGN: The study included 30 patients with 37 HCC who had undergone PAI. Baseline cytomorphology of HCC was evaluated by needle aspiration in all cases. PAI under ultrasound guidance was done every three to seven days. Upon completion of PAI, fine needle aspiration cytology was performed and followed by helical CT within two weeks. The degeneration of HCC after PAI was classified into two grades. Grade 1 showed incomplete degeneration (99% of nuclear area); grade 2 showed complete degeneration or severe degeneration with cell debris or amorphous material only. The specimens were stained with Riu's method (Romanowsky system). RESULTS: The cytologic changes after PAI included decreased cell number, reduced cellular aggregation, degeneration of cytoplasm and nucleus, and eosinophilic or basophilic background in all tumors. In all the 37 tumors without enhancement on helical CT, grade 2 degeneration was detected. CONCLUSION: Our results reveal that grade 2 degeneration alone, demonstrated cytologically, could indicate almost complete necrosis of HCC after PAI, probably implying no need for booster PAI.

Acetic Acid↗

PubMedDate not supplied

Disseminated histoplasmosis presenting as bilateral adrenal masses.

Histoplasma capsulatum is a universal dimorphic fungus found mainly in soil contaminated with excrement of birds and bats. Bilateral adrenal masses with massive tissue destruction are a rare primary presentation of disseminated histoplasmosis. As it behaves as an opportunistic pathogen there is a higher susceptibility for dissemination on those patients with immunodeficiency or immunosuppression. We report a case in an elderly diabetic patient with bilateral adrenal enlargement, diagnosed as histoplasmosis only after surgical exploration, with symptoms probably occurring at least 60 years after the original infection. She was successfully treated with itraconazole.

Adrenal Gland Diseases↗

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Morphologic effects of thio-TEPA on mammalian urothelium. Changes in abnormal cells.

Morphologic changes induced by thio-TEPA were examined in animals with chemically induced neoplasms. Both toxic and metabolic effects were documented. Degeneration, vacuolization and increased exfoliation (toxic) were most prominent, occurred within 48 hours of exposure, and tended to subside after removal of the drug. Nuclear changes (metabolic) were rare and occurred late. Neither toxic nor metabolic effects were specific for thio-TEPA: both could be detected in control animals receiving saline. The metabolic effects of thio-TEPA are not sufficiently widespread to prevent tumor growth.

Animals↗

PubMedDate not supplied

Physiological knock-knee in preschool children: prevalence, correlating factors, gait analysis, and clinical significance.

Physiological knock-knee (PKK) was categorized by measuring intermalleolar distance (IMD), a clinically simple method, to evaluate the prevalence and correlating factors in 305 preschool children. The prevalence in this cross-sectional study was relatively high, and it was age related (p = 0.002; 64, 44, and 34% for ages 3-4, 4-5, and 5-6 years, respectively). The following factors were correlated with PKK: use of walking chair early (p = 0.0001), independently walked late (p = 0.0005), dependently walked longer (p = 0.0001), concurrence with flatfoot (p = 0.001), and angular deformity (toe in/out, p = 0.03). Gait analysis, with spatiotemporal, kinematics, and kinetics parameters, was performed to evaluate the ambulatory significance. Preschool children with PKK have a shorter stride length (p = 0.02) and a slower walking speed (p = 0.004). Dynamic hyperextension of the knee is noted for 8 degrees during the whole gait cycle (p < 0.05). We conclude that PKK is a variable that should be considered in the development of mature gait for preschool children.

Child↗

PubMedDate not supplied

Correlating factors and clinical significance of flexible flatfoot in preschool children.

To elucidate the correlating factors and clinical significance of flexible flatfoot (FF) in preschool children of Taiwan, a cross-sectional study was conducted in a research laboratory equipped with a gait analysis facility. Altogether, 377 preschool children (201 boys, 176 girls), ranging in age from 2 to 6 years, were enrolled in this investigation. The results show that age, height, weight, foot progression angle, occurrence of physical knock-knee, and joint laxity score correlate with FF. Children with FF, compared with children without, performed physical tasks poorly and walked slowly, as determined by gait parameters. The FF should not simply be regarded as a problem of static alignment of the ankle and foot complex, but may be the consequence of a dynamic functional change of the lower extremity. Better understanding of the correlating factors and the clinical relevance of FF may prove helpful in deciding on the most appropriate treatment for a particular patient.

Age Factors↗

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The management of anorectal malformations.

From 1982 to 1990, 120 cases of anorectal malformation (84 males and 36 females) were admitted to Mackay Memorial Hospital; 101 cases were corrected surgically. Among these, 40 cases were high (H) or intermediate (I) type, and 61 cases were low (L) type. In the 40 cases of the H and I type, 13 (Group 1) received Stephens' procedure (SPR) and the remaining 27 (Group 2) received Peña's procedure (PSARP). For the L type, translocation anoplasty, cut-back anoplasty and limited PSARP were employed in 10, 45 and 6 cases, respectively. Anorectal continence results were evaluated by Kiesewetter's criteria. In Group 1, the results were good in 25%, fair in 17% and poor in 58%. In Group 2, the results were good in 70% and fair in 30%. In addition to better anorectal continence, the PSARP resulted in a lower rate of major complications. In the L type, the results were excellent without significant difference among the types of surgery employed.

Anal Canal↗

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Color flow mapping in ventricular septal defect: correlation of hemodynamic data and shunt flow area.

To evaluate the efficacy of two-dimensional Doppler echocardiography in assessing the severity of isolated ventricular septal defect, 31 children were studied within 24 hours of cardiac catheterization. The shunt flow area at peak systole (PSFA), diastole (DFA) and end-diastole (EDFA) and maximal shunt flow area (MSFA) were measured with frame-by-frame technique and corrected with body surface area and heart rate. The Qp/Qs ratio was calculated by the Fick's principle. Simultaneous pressures at peak systole (PSP), diastole (DP) and end-diastole (EDP) were recorded in the left (LV) and right ventricle (RV). The Qp/Qs ratio was correlated well with MFA (p = 0.05), MFA/BSA (p less than 0.001), PSFA/BSA (p less than 0.001), MFA/HR (p less than 0.05), MFA/BSA, HR (p less than 0.001), PSFA/BSA and HR (p,0.001). The PSP gradient between LV and RV was inversely correlated with MFA/BSA and PSFA/BSA (p less than 0.05) and HR (p less than 0.05). Two-dimensional Doppler echocardiography can provide a useful information of hemodynamic changes in children with isolated ventricular septal defect.

Adolescent↗

PubMedDate not supplied

Morphologic effects of thio-TEPA on mouse urothelium.

The urothelial changes induced by intravesical instillation of thio-TEPA into experimental animals were studied by cytologic, light microscopic, and electron microscopic techniques. Cells and tissue from treated and untreated groups were compared using a total of 54 discriminators. There were few consistent differences. Cells with marked nuclear atypia were not identified. The results indicate that thio-TEPA has little effect on non-diseased bladders. The atypical cells occasionally present in specimens from thio-TEPA treated bladders apparently do no emanate from normal urothelium.

Animals↗

PubMedDate not supplied

Atlantoaxial rotatory instability secondary to odontoid hypoplasia as a cause of acute torticollis in children: report of one case.

One patient with the chief complaint of acute torticollis was diagnosed as atlantoaxial rotatory instability secondary to hypoplasia of odontoid process. The diagnosis was confirmed by cervical radiography and computerized tomography. The attack of wryneck was first misdiagnosed as cervical muscle strain. Detailed physical examination revealed the tenderness to be located not at the sternocleidomastoid muscle. The fixed and painful rotatory deformity strongly indicated a cervical spinal lesion. Plain radiographic tests of the cervical spine revealed atlantoaxial rotational subluxation. Hypoplasia of the odontoid process, rarely reported as associated with this problem, was noted. Computerized tomographic tests further delineated the pathological alterations. Treatment with gentle reduction and traction for three days, and maintenance with neck collar for the three subsequent weeks, achieved a successful solution. No recurrence was noted after a two-year observation period.

Acute Disease↗